Typically a mine is comprised of two parts — the mine (the hole in the ground), and the refinery.
The refinery does just that, it refines.
The input is the ore from the mine, and the output is the ‘valuable’ mineral, and the waste, the tailings.
Unlike open cast mines, underground mines require that the underground water be pumped out and treated before being recycled into the refining process, or discharged to waste.
As has been experienced lately in the Bowen Basin, even open cast coal mines can flood due to storms and the forces of nature, and this water also needs to be treated before disposal.
The method of refining is determined primarily by the mineral(s) involved and can include one, or a number of processes such as leaching, flotation, settling, calcification, CIP and more.
In almost all cases, aggressive chemicals are used to stimulate the chemical reaction process, sulphuric acid, nitric acid, cyanide, or are used to assist the flotation and settling processes.
Not all doom and gloom
Today our Press is filled with the news of mines being places on ‘care and maintenance’. At last count over 500 mines across the country are ‘closed’.
Mines cannot be closed ‘easily’.
Most of the hazards that face mines when the mine is in operation do not ‘go away’ when a mine is ‘closed’.
Underground water builds up.
Rain fills open cast mines.
Chemicals continue to leach into surrounding areas, and finally end up in the rivers.
Chemicals have to be stored and monitored. And, of course, all the plant and machinery has to be serviced in anticipation of an increase in the prices of the minerals, and the bringing to life of the mine.
It was interesting to read recently that Andrew Forrest, the Fortesque chief, was forecasting that we are ‘at around bottom of the market’.
The implication, and this is borne out by discussion of stimulus packages in China, is that many of our mines on ‘care and maintenance’ will need to be ‘maintained’ in excellent shape for a quick startup — hopefully within the next 12 months.
So why all the gloom? All the process measurement instrumentation (and valves, and drives) has to be maintained in good working order.
Level measurement in the chemical storage tanks, flow measurement of the pumped-out water, water treatment, pH, conductivity, temperature — all very important parameters that must continue to be monitored during ‘care and maintenance’.
Already there are companies that specialise in ‘care and maintenance’ of mines, and for a fee, the mine owners can walk away from their investment until the boom returns.
An interesting opportunity exists for technicians with instrumentation (and electrical) skills to sub-contract to the ‘care and maintenance’ companies and provide these services. And the good news from a vendor perspective, it that it is not going to be about price! But it will be about reliability, robustness, fit-for-purpose, and maintenance reduction.
Every cloud has a silver (or maybe gold, or uranium) lining.